1. Field of the Invention
The present invention relates to an image-pickup apparatus such as a digital camera, and more particularly to an image-pickup apparatus having a shutter apparatus.
2. Description of the Related Art
A shutter apparatus has a leading blade group (hereinafter referred to as “leading blade”) that travels from a state in which an opening of a shutter closes (hereinafter referred to as “closed state”) to a state in which the opening opens (hereinafter referred to as “opened state”), and a trailing blade group (hereinafter referred to as “trailing blade”) that travels from the opened state to the closed state. Each of the leading and the trailing blades is configured by a plural of light shielding blades, and the light shielding blades are coupled by an arm so as to form a parallel link and are translated in a travelling direction.
Some image-pickup apparatuses including the shutter apparatus have a live view function in which the shutter apparatus is opened before shooting and a dynamic picture image generated by an output from an image-pickup element is displayed on a monitor in the back side of the camera.
Japanese Patent Laid-open No. 2009-31513 discloses an image-pickup apparatus that controls an applied voltage to a motor when the image-pickup apparatus transits from stop phase to live view phase so as to reduce a release time lag.
However, Japanese Patent Laid-open No. 2009-31513 does not disclose an optimum applied voltage to the motor from live view phase until shooting phase.
Additionally, an arm of the shutter apparatus is driven by a driving lever biased by a spring. The driving lever has an amateur attracted to an energized electromagnet at a position where the spring is charged.
The driving lever turns by biasing of the spring when energizing to the electromagnet is stopped, and the plurality of the light shielding blades are travelled via the arm. The charge mechanism including the motor returns the driving lever to the charge position while charging the spring, and returns the leading and the trailing blades to each starting position when the exposure by travelling of the leading and the trailing blades ends.
Japanese Patent Laid-open No. 2010-164903 discloses a configuration that cam lift of a cum surface traced by the driving lever at the end of the charge operation is smaller than cam lift of a cum surface traced by the driving lever at the beginning of the charge operation, and have achieved to drop the collision speed of the amateur and the electromagnet.
However, the image-pickup apparatus of Japanese Patent Laid-open No. 2010-164903 have caused accuracy change when the release frequency increases because the driving lever is not fully slowed down at the end of the charge operation.